This invention relates to the collection and storage of biological fluids. The invention more particularly relates to a unique method and apparatus for collecting fluids such as blood, serum, plasma and the like into flexible containers made from plastic, rubberized cloth and the like.
In accordance with conventional practices, blood is taken from human donors or animals and stored in sterilized glass bottles and/or flexible containers. Blood is removed from the body of the donor through a phlebotomy needle inserted into a vein, the needle being connected to the storage container by means of flexible tubing. The glass bottles which are used for this purpose require special construction and are therefore relatively costly. In order to reuse these bottles a careful sterilization process must be effected using special equipment. Further glass bottles are easily breakable and are not adapted to fit into small or irregular spaces.
In recent years, the use of flexible containers have found wide spread use for the storage of blood. The most commonly used type of flexible containers are manufactured from a plastic material. Collapsible containers by their very nature are incapable of being previously evacuated. To solve this problem, the flexible containers have been used in conjunction with blood extracting equipment which includes a vacuum chamber designed to receive the flexible container therein. The vacuum chamber includes means for drawing vacuum therein during the extracting operation. This type of system permits the collection of blood into a flexible container under the influence of a vacuum. However, as the flexible container is being filled, it expands in volume into contact with the sides of the vacuum chamber making it quite difficult to remove the blood filled container from the chamber upon completion of the blood draw. If the vacuum chamber is increased in size to solve the above problem then there is no control of the upper limit of the quantity of blood drawn.
In order to disclose the present invention in an environment which utilizes its potential to a maximum, it will be disclosed for use in the collection of blood from an animal, such as a fetal calf. It has been the heretofore practice to collect blood from the fetal calf in glass vacuum bottles of the type mentioned hereinabove. In addition to the disadvantages previously mentioned with regard to glass bottles, they are of fixed dimensions and can only collect a fixed amount of blood. Since the size of the fetal calf and the amount of blood available to be collected varies considerably, it has heretofore been sometimes necessary to puncture the calf a second time to maximize the blood drawn from each calf. A second puncture increases evacuation time and the chances of contamination. A further problem which has presented itself is that the use of conventional glass bottles frequently results in hemolysis. The initial excess vacuum present in the bottle causes rupture of certain blood cells which releases hemoglobin into the collected blood, which substantially reduces its use in many medical applications.
Although the present invention will be hereinafter described in the environment of collecting blood from a fetal calf for purposes of disclosing a specific use, it is contemplated that the teachings of the invention are equally applicable for drawing various types of biological fluids from humans and other animals.